14
votes
How is gas flow through (extremely long) pipelines monitored and controlled?
It's important to remember that these pipelines don't exist as a single isolated line and will have a number of branches that tie into the main pipeline and split off for gas to be sold to different ...
10
votes
Accepted
Is it possible to increase the heat output of a gas stove by connecting two gas supply canisters to it at the same time, and is it safe to do so?
is it possible to increase the heat output of the burner by
connecting two low-pressure supplies in parallel via a
T-piece like this one?
The primary factor is gas pressure at the tee. If the ...
9
votes
Is it possible to increase the heat output of a gas stove by connecting two gas supply canisters to it at the same time, and is it safe to do so?
No, connecting two tanks together will not double the flow.
The regulators fitted to tanks limit the pressure and flow rate so all you do is double the amount of gas the burner has available ie ...
8
votes
Accepted
How to know whether the flow is supersonic in a nozzle?
From my brief involvement in shocks, I think the most likely solution would be to image the exhaust, probably optically, but maybe using interferometry or something depending on what the exhaust is. ...
7
votes
How can I turn home gas (LPG) from liquid to gas?
Lighters usually use Butane.
Gas bottles use some or all Propane.
Propane pressures are MUCH higher.
A plastic 'tank' filled with Propane would probably explode.
As size increases the container ...
6
votes
Accepted
Determining pressures of a compressible gas
Seriously?! :D
There are going to be two parts to the solution you are looking for,
A) Till the steak is in the cannon
B) The steak leaves the cannon, is into the air and cooking starts
A) ...
5
votes
Accepted
Typical power consumption of large compressor
The work is surely path dependent; you can estimate a fast passable value in two way.
Isothermal, as in the case when several stages with intercoolers are used
(SI Units)
KWiso = 2.78*10^-4 * (...
5
votes
Accepted
Is steel air (argon) tight?
Steel is routinely used for high pressure storage of industrial argon. For practical purposes it is certainly 'gas tight' although there may be a certain amount of atomic level diffusion into the ...
5
votes
Accepted
What material is used to make gas pipes?
In my admittedly limited experience working with plumbers, natural gas pipes are typically made from galvanized steel for interior work, or from black steel pipe for underground. Last-leg fittings and ...
5
votes
Accepted
How do gas flow regulators avoid choking?
The short answer is that they don't. Choking is not a bad thing. For a gas flow regulator, it's actually a good thing, because under choking conditions, the mass-flow rate is no longer dependent on ...
5
votes
Accepted
Multi-gas barometric height formula in isotope separation devices?
The barometric height formula is defined as:
$$ p(z) = p(0)\exp(-Mgz/(RT))$$
For a centrifuge the upper expression is transformed to:
$$ p(r) = p(0)\exp(M\omega^2r^2/(2RT))$$
As you see the $g$ is ...
5
votes
Easily compute a good approximation of heat conductivity of cooled semi-vacuum (water vapor + air)
In the molecular flow region of pressure, the thermal conductivity of an ideal, monatomic gas is obtained by this equation.
$$
k = \frac{1}{\pi^{3/2} d^2}\sqrt{k_B^3T/m}
$$
where $d$ is the ...
5
votes
Would pumping down (below 0 psi) on a gas cylinder regulator cause it to break?
I doubt there would be a problem. That type of gauge has a bourdon tube inside that has a curved flattened tube. The tube goes from flat to round as the pressure increases which straightens out the ...
4
votes
How is gas flow through (extremely long) pipelines monitored and controlled?
For question 1, as far as I recall, fiscal metering of long hydrocarbon gas pipelines is done with coriolis effect mass flow meters. To calculate Mach number, all that would be required is the mass ...
Community wiki
4
votes
Accepted
How do you prevent ignition of the gas-air mixture before it reaches the burner nozzle?
Depending on fuel, a flame has a certain propagation speed - the speed with which the flame wanders through the medium. If the fuel - oxygen mixture moves faster through the pipe than the propagation ...
4
votes
Can mercury escape undectectably from a CFL bulb? or does it have to shatter for the mercury to be liberated?
If there were a crack in the glass, then the pressure difference would first cause air to flow into the lamp, which would cause it to stop working (both the mercury and the low pressure are necessary)....
3
votes
Accepted
Service Life of a Flashback Arrestor
The manufacturer says this about maintanence:
annual testing of the non-return valve, body leak tightness
and flow capacity is recommended
WITT is happy to supply special test equipment
...
3
votes
Accepted
Pressure drop due to mass loss
You can't use the ideal gas law in an open system, but you can use Bernoulli's equation.
Starting with the conservation of energy:
$$ E_{in} = E_{out} $$
We have one source in and two sources ...
3
votes
How to know whether the flow is supersonic in a nozzle?
That is a really nice thought experiment! In general I would argue that you only need to know:
Total-Pressure ( $p_t$ of your supply)
Static/Ambient Pressure ( $p_\infty$into which you are expanding)
...
3
votes
Accepted
Diesel or Gasoline? Which one is more dangerous to our health?
1) In an engineering context efficiency has a very specific meaning ie it is the ratio between the energy you put into a system and the useful work that you get out. In itself this doesn't tell you ...
3
votes
Will natural gas or propane generators also run off of methane?
natural gas is methane, so no problems there. an internal combustion engine that is equipped to operate on gasoline can be converted easily to run on gaseous fuels and the conversion kits usually ...
3
votes
Accepted
Do pressurised cans still pose a risk to bursting in normal conditions, but after being exposed to heat?
Assume that high temperature causes no chemical reactions in the contents or between the contents and the can.
High temperature will increase the pressure in the can. Assume the can is fully ...
3
votes
Does the shape of a car really matter for how much gasoline it drinks?
The difference is in the drag coefficient.
Typical drag coefficient of the 50's cars have been in the range of 0.38 to 0.42 or so.
typical drag coefficient of modern cars even the ones not renowned ...
3
votes
Gas kitchen stove in skyscrapers
Gas is odorized ( mercaptans ) which can be detected at a ppb level. The great majority of people notice the smell and take some corrective action. On the otherhand ,whenever you make something fool ...
2
votes
Can using different types of alcohol in a cloud chamber produce different particle tracks?
The only major difference the alcohol choice will make is the ionization energy. While the ionization energy for Methanol is 10.85 (source), ethanol is 10.62 eV, while Isopropyl is only 10.10 eV. ...
2
votes
Pressure drop due to mass loss
Divide both sides of the equation by time. This allows you to use flow rates, but does not account for friction, so you will have to account for that with your standard hydraulic formulas.
2
votes
Calculate pneumatic cylinder dimensions from work done
It is possible to calculate this under the assumption that all of the energy from the expansion goes into mechanical energy instead of being lost to heat transfer through the walls. In this case the ...
2
votes
Pressure drop across column in gas phase: what changes?
Frictional Heat!
In simple terms, the pressure drop that is observed is a result of the friction between the moving fluid, and the stationary walls and column packing.
This friction reduces the ...
2
votes
Working out pressure drop from leak rate
The rate of gas leakage depends on the pressure difference, and in your setup it looks like the pressure difference is constantly decreasing as the test is running. This means that the leak rate ...
2
votes
Is an Explosion Proof Circuit Breaker Panel Required at a Gas Station?
I see nothing in your picture to indicate that the circuit breakers need to be explosion proof. They don't appear to be in a zone 0 location, nor would I expect that any explosion proof volume would ...
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